Carburetor synchronizing device



Oct. 15, 1957 E. E. BRUSH CARBURETOR SYNCHRONIZING DEVICE INVENTOR A TOR/Vf y 5 United States atent Ofiice 2,809,516 Patented Oct. 15, 1957 2309,5 16 a t cmnnr roiz'smcnnomzme DEVICE "Edward Brush, College Station, Tex. Application May'11, 1 954,'Serial N0. 428,93 a Claims. ierra-11 s 'Thepresent invention relates to carburetor synchron- "throttle settings ofmultiple carburetors may ,quickly and accurately be synchronized.

It is .yet a further object ofthe presentinvention to provide :such taasynchroniz ing deviceffor synchronizing multiple carburetors by which very rapid visualandprecise indication of relative throttle. positions .in multiple carburetors may be .obtained and synchronized by directly comparing the :entering an velocitiesrof thecarburetors.

Yet a .further object of the present invention is the provision of a very rapid visual. and precise means for adjusting throttle ,positions of two ormore carburetors.

A furthersobject of :the present invention .isthe, .provision of a very rapid visual means for synchronizing the .throttle settings of more than two identical carburetors bylmatching them in overlappingpairs.

It is yet a further-object of the ,present invention to provide -such a carburetor synchronizing device which is inexpensive to construct and maintain, whichis accurate and dependable in operation and by whichpreciseread- .ings may beobtained ina minimum of time.

Other and further objectsand features. of the invention will be apparent from the following description of an example of the invention, given for the purpose of disclosure, taken in conjunction with the accompanying drawing, in which like character references designate like parts throughout the several views, and where:

Figure 1 illustrates a synchronizing device for carburetors.constructed according to the -inventionand shown in .frontelevation attachedwto a pair .of carburetors,

Figure 2 is across-sectional :view taken along the line 2-2 of Figure 1, looking in the direction of the arrows,

Figure 3 -is a sectional view taken along the line 3-3 of Figure 1 and looking in the direction of the arrows, and

Figure 4 is a fragmentary front elevation illustrating a --differen't manner of supporting the manometer when in use.

Throughout the --specification the terms synchroniza ti'on and synchronize are nsed to designate that the respective "throttle settings are adjusted so thatthese set- "tings provide equal'air flow -in -the-respective carburetors.

Referring now to the drawing, a pair of matched venturi tubes 10 are secured to a pair of carburetors 12 to be synchronized which-have had their respective air cleaners and air cleaner manifolds previously removed. While the venturi tubes may be secured in any desired manner to the air intakes of the carburetors 12, this may be accomplished by means of the plates 14 being provided with the bosses 16 projecting rearwardly therefrom, which are '2 positionedin the air intakesf18 of 'the carburetors 12. For attachment of the venturi tubes1'0 to the carburetors '12, the -bosses 16 may be providedwith a plastic or Jresilient packing material 20 so that they fit snugly in the air intakes18 in the carburetors '12. In securing the venturi tubes 10 to the carburetors 12, it may be necessary to-place a sleeve (not shown) over the exposed .ends of the carburetors, such as a rubber pipe, so that the bosses 16 may be inserted in the air intakes, such as where a butterfly valve and the like would] prevent this insertion. The throatsl22 of 'the venturi'tubes 10 are thus maintained in alignment with the air intakes. of the car-. buretors 12 and all air passing or drawn into the carburetors 12 must .pass through the throats 22 of each venturi tubel10.

While reference .is made to the venturi tubes 10, .it will be understood that the expansion cones 23.1nay be eliminated and, lhence, contracting nozzles are suitable without the expansion .cones and the operation .is the sameforboih.

.It willbe understood, of course, that the venturitubes 10 may be secured to the carburetors :12 in any satisfac- "tory manner; however, the arrangement described is presently preferred in view of the rapidity by which they .may be secured "to the carburetors and their-efficiency in snugly holding the venturi throats '22 in the air intakes 18 of the carburetors so that an of the air drawn into the carburetors 12 passes through the throats 22 of the venturiitubes 1'0.

. A tube like projectionf2'4aextends upwardly 'f rorneaeh venturi tube 10 and has a passageway '26 extending into the throat .22 of each venturi tube 10. (Secured to the "upper ends of the tube like projections 24are the flexible tubes or conduits 2 8, which maybe formedaof any suitable flexible material, such as rubber and the like, which tubes have their other ends secured .to the upstanding ends of opposite legs 29 of the 'U-shapedwmanometer tube 30. Thus, a difference in fluid level in the manometer 'legs 29, will be apparent if the air yelocityfin one'venturi tube 110 is differentfromthat in the other.

The U-shaped manometer tube 30lislldisp'osed on a manometer plate '32 which has the. parallel or horizontal scribe lines '34 so that the fluid level in the legs 29 of the manometerf30 may visually and readily 'be adjusted to the same height in each manome'terleg'29.

The manometer 30 and manometer plate 32 may be secured to or disposed with respect to the motor in any desired or satisfactory manner; however, it is advanta geous to provide an extension 36 of themanometer plate 32 which may be provided with an aperture through whichawing nutass'embly'38 extends'so thattheman'ome- 'ter plate may adjustably be 'securedit'o the face plates 14 of one of the venturi tubes 10. Thus, afterthe face plates 14 are attached to the carburetors 12, 'bymerely loosening. the wing nut 38, the manometerplate 32 may 'be adjustedinto a substantially vertical position and the wing nut 38 tightenedso that accurate adjustmentsmay be made. Figure 4 illustra'testhe manometer plate 32 connected to a structural element of thevmotor-39 and, if desired, a simple clip may be substituted for the, wing nut assembly 38 and projection '36 so that the manometer may be attached as desired, although any means "of att'achm'ent ma-y be omitted.

tors 12 and the bosses 16 may be inserted in the air in takes of the carburetors 12 by means of the arrangement described. The wing nut 38rnay be loosened, if necessary, and the manometer 32 adjusted to level. As mentioned previously, the venturi tubes are matched and adjusted in manufacture so that air flow of a given velocity produces the same static pressure in the throat 22 of each venturi tube 10.

With the engine operating at idling speed and the throttle interconnect clamp (not shown) released, a difference in fluid level in the manometer legs 29 will be apparent if the air velocity in one venturi tube is different from that in the other inasmuch as the venturi tubes are connected to oppositelegs 29 of the manometer 30 by means of the'tubes 28. Adjustment of the throttle stop screws (not shown) on the two carburetors will vary the throttling and thus the air velocity through, the venturi tubes 10 into the carburetors. If the liquid level in the two manometer legs is not equal, one or both of the respective throttle screws may be adjusted until this level is equal, at which time the air velocity through the throats 22 of the venturi tubes 10 is the same and the'throttle settings are synchronized. The throttle shafts (not shown) may then be interconnected to the throttle interconnect clamp with the, assurance that the throttles will be synchronized in all'positions. The synchronizing device may then be removed from the carburetors 12 by merely pullingoutwardly on the venturi face plates 14 and, in the event there are additional carburetors to be synchronized, one of the face plates 14 may be removed from a carburetor 12 and attached to another carburetor, the additional carburetor adjusted by adjusting its throttle stop screws so that the liquid level in the manometer legs 29 is level in the manner mentioned. The throttle shaft ofthis third 'carburetor'may then be interconnected With the throttle interconnect clamp as previously explained. This, of course, may be repeated as many times as desired, that is, synchronizing the throttle settings of more, than two identical carburetors by matching them in overlapping pairs and utilizing one or other of the synchronized carburetors as the reference for the throttle adjustment of the others. After the desired adjustment or What is claimed is:

1. A device for synchronizing the throttle adjustments of two or more carburetors comprising, a pair of matched venturi tubes, means by which one each of the venturi tubes may be secured in an air intake of each of said carburetors so that air drawn into the carburetors passes through the venturi tube secured thereto, a U-shaped manometer, means connecting a throat of each venturi tube to a different leg of the manometer so that the ratio of air passing through the venturi tubes is visibly indicated by the manometer whereby adjustment of one or more of the throttle settings of the carburetors until the liquid level in the manometer legs is equal synchronizes the throttle settings of said carburetors.

2. A device for synchronizing the throttle adjustments of two or more carburetors comprising, a pair of matched venturi tubes, a first projection extending from each, tube adapted to snugly fit in an air intake of each carburetor whereby one each of the venturi'tubes may be secured to one each of the carburetors and air drawn into the car- 'buretors passes through the venturi tube secured thereto,

' of said carburetors.

3. The device of claim 2 in which the first projection is provided with resilient packing which resiliently engages the air intake for rapid sealing attachment and detachment of the venturi tubes thereto.

4. A device for synchronizing the throttle adjustments of two or more carburetors comprising, a pair of matched venturi tubes each having a face plate thereon, a hollow boss extending from one each of said venturi tubes, said boss adapted to be inserted into the air intake of one each of said carburetors for securing one each of the venturi tubes to one each of the carburetors so that air drawn into the carburetors passes through its respective venturi tube, a manometer face plate provided with scribe lines, a U-shaped manometer secured to the manometer face plate, means for adjustably securing the manometer plate be synchronized, one of the venturi tubes or contracting nozzles may be secured as mentioned to a third carburetor and the throttle setting of the third carburetor adjusted until the liquid is level in the manometer. This, of course, may be repeated as often as desired by then moving either of the venturi tubes.

The present invention, therefore, is well suited to carry out the objects and attain the advantages mentioned, as well as others inherent therein.

While a single example of the invention has been given for the purpose of disclosure, numerous changes in details, rearrangements 'of parts and steps may be made which will suggest themselves to those skilled in the art and which are encompassed within'the spirit of the inven tion and the scope of the appended claims.

to one of the venturi face plates, a projection extending 'upwardly from each venturi tube, each projection provided with a passage extending into the throat thereof, and flexible conduits attached to each of the projections and having their other ends attached to the upstanding free'extremities of each leg of the manometer whereby the ratio of air passing through the venturi tubes is visibly indicated by liquid level in the manometer tubes, adjustment of one or more of the throttle settings of the carburetors until the liquid level therein is equal synchronizing the throttle settings of said carburetors.

References Cited in the file of this patent 2,597,231 -Ede1in' May 20, 1952 

